U.S. patent number 5,343,841 [Application Number 07/934,649] was granted by the patent office on 1994-09-06 for intake control device of internal combustion engine.
This patent grant is currently assigned to Nippondenso Co., Ltd.. Invention is credited to Isao Hattori, Tokio Kohama, Shigeo Nomura, Yurio Nomura.
United States Patent |
5,343,841 |
Hattori , et al. |
September 6, 1994 |
Intake control device of internal combustion engine
Abstract
The present invention provides an intake control valve which is
able to reduce intake air leakage, control the amount of intake air
with high accuracy, and to allow easy installation to an intake
manifold. The intake control valve of an intake control device
according to the present invention has a valve body, a case, and an
actuator. The valve body is rotatably installed in the case,
opening and closing an openingclosing passage formed in the case.
The case is fitted with the actuator, which functions to rotate the
valve body. In the meantime, the intake manifold is provided for a
mounting bore formed for insertion of the case. On the outer side
of the case are installed sealing members, which contact the wall
surface of the mounting bore to prevent air leakage. The intake
control valve is installed in the mounting bore formed in the
intake manifold after assembling the valve body, the case and the
actuator into one unit.
Inventors: |
Hattori; Isao (Gifu,
JP), Nomura; Yurio (Nagoya, JP), Nomura;
Shigeo (Toyohashi, JP), Kohama; Tokio (Nishio,
JP) |
Assignee: |
Nippondenso Co., Ltd. (Kariya,
JP)
|
Family
ID: |
14334425 |
Appl.
No.: |
07/934,649 |
Filed: |
March 1, 1993 |
PCT
Filed: |
April 27, 1992 |
PCT No.: |
PCT/JP92/00553 |
371
Date: |
March 01, 1993 |
102(e)
Date: |
March 01, 1993 |
PCT
Pub. No.: |
WO92/19853 |
PCT
Pub. Date: |
November 12, 1992 |
Foreign Application Priority Data
|
|
|
|
|
May 8, 1991 [JP] |
|
|
3-102696 |
|
Current U.S.
Class: |
123/403; 123/405;
137/454.6; 137/883 |
Current CPC
Class: |
F02D
9/10 (20130101); F02D 9/16 (20130101); F02B
29/083 (20130101); Y02T 10/146 (20130101); F05C
2201/021 (20130101); Y02T 10/12 (20130101); Y10T
137/87877 (20150401); Y10T 137/7668 (20150401) |
Current International
Class: |
F02D
9/16 (20060101); F02B 29/08 (20060101); F02D
9/10 (20060101); F02D 9/08 (20060101); F02B
29/00 (20060101); F02D 033/02 (); F02D
009/16 () |
Field of
Search: |
;123/52MF,337,403,405,585 ;137/454.6,870,883 ;251/129.11,309 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
2456214 |
|
Dec 1980 |
|
FR |
|
54-88929 |
|
Jun 1979 |
|
JP |
|
56-113006 |
|
Sep 1981 |
|
JP |
|
61-31146 |
|
Sep 1986 |
|
JP |
|
63-65138 |
|
Mar 1988 |
|
JP |
|
1267316 |
|
Oct 1989 |
|
JP |
|
2140419 |
|
May 1990 |
|
JP |
|
235090 |
|
Sep 1990 |
|
JP |
|
2223634 |
|
Sep 1990 |
|
JP |
|
41420 |
|
Jan 1992 |
|
JP |
|
8302800 |
|
Aug 1983 |
|
WO |
|
Other References
Patent Abstract of Japan, vol. 12, No. 014 (M-659) Jan. 16, 1988,
JP-A-62 174 531, Jul. 1988. .
Patent Abstract of Japan, vol. 12, No. 014 (M-659) Jan. 16, 1988,
JP-A-62 174 513, Jul. 1987..
|
Primary Examiner: Argenbright; Tony M.
Attorney, Agent or Firm: Cushman, Darby & Cushman
Claims
We claim:
1. An intake control device of an internal combustion engine
including an intake control valve mounted in an intake air passage
of said internal combustion engine and driven in timed relation
with rotation of said internal combustion engine to open and close
said intake air passage, and an intake manifold having said intake
air passage formed inside and a mounting bore communicating with
the upstream and downstream sides of said intake air passage, said
intake control valve comprising:
a case inserted in said mounting bore and having an inlet and an
outlet communicating with said upstream and downstream sides of
said intake air passage in said mounting bore and having an
opening-closing passage connecting said inlet to said outlet;
a valve body rotatably mounted in said case and opening and closing
said opening-closing passage; and
driving means for rotating said valve body,
said intake control valve being driven in timed relation with the
operation of an intake valve mounted at the inlet of a combustion
chamber of said internal combustion engine, controlling, by each
intake stroke, the amount of intake air being supplied into said
combustion chamber of said internal combustion engine.
2. An intake control device of an internal combustion engine as
claimed in claim 1, wherein an airtight means is provided between
said case and said mounting bore to keep airtightness between said
upstream and downstream sides of said intake air passage.
3. An intake control device of an internal combustion engine as
claimed in claim 1, wherein said inlet and said outlet of said case
are provided with chambers expanding toward said intake air
passage.
4. An intake control device of an internal combustion engine as
claimed in claim 1, wherein said opening-closing passage in said
case is formed as a passage having a circular section communicating
between said inlet and said outlet.
5. An intake control device of an internal combustion engine as
claimed in claim 4, wherein said valve body is a disk valve
inserted in said passage having the circular section.
6. An intake control device of an internal combustion engine
including an intake control valve mounted in an intake air passage
of said internal combustion engine and driven in timed relation
with rotation of said internal combustion engine to open and close
said intake air passage, and an intake manifold having said intake
air passage formed inside and a mounting bore communicating with
the upstream and downstream sides of said intake air passage; said
intake control valve comprising:
a case inserted in said mounting bore and having an inlet and an
outlet communicating with said upstream and downstream sides of
said intake air passage in said mounting bore and having an
opening-closing passage connecting said inlet to said outlet;
a valve body rotatably mounted in said case and opening and closing
said opening-closing passage; and
driving means for rotating said valve body,
said opening-closing passage in said case being of cylindrical form
with said inlet and said outlet opening in a cylindrical
surface,
said valve body being a cylindrical valve inserted in said
cylindrical opening-closing passage.
7. An intake control device of an internal combustion engine as
claimed in claim 6, wherein an airtight means is provided between
said case and said mounting bore to keep airtightness between said
upstream and downstream sides of said intake air passage.
8. An intake control device of an internal combustion engine as
claimed in claim 6, wherein said inlet and said outlet of said case
are provided with chambers expanding toward said intake air
passage.
9. An intake control device of an internal combustion engine as
claimed in claim 6, wherein said opening-closing passage in said
case is formed as a passage having a circular section communicating
between said inlet and said outlet.
10. An intake control device of an internal combustion engine as
claimed in claim 9, wherein said valve body is a disk valve
inserted in said passage having the circular section.
11. An intake control device of an internal combustion engine
including an intake control valve mounted in an intake air passage
of said internal combustion engine and driven in timed relation
with rotation of said internal combustion engine to open and close
said intake air passage, and an intake manifold having said intake
air passage formed inside and a mounting bore communicating with
the upstream and downstream sides of said intake air passage; said
intake control valve comprising:
a case inserted in said mounting bore and having an inlet and an
outlet communicating with said upstream and downstream sides of
said intake air passage in said mounting bore and having an
opening-closing passage connecting said inlet to said outlet;
a valve body rotatably mounted in said case and opening and closing
said opening-closing passage;
driving means for rotating said valve body; and
connecting means for connecting said case to said intake air
passage relatively movably within a specific range.
12. An intake control device of an internal combustion engine as
claimed in claim 11, wherein said inlet and said outlet of said
case are provided with chambers expanding toward said intake air
passage.
13. An intake control device of an internal combustion engine as
claimed in claim 11, wherein said opening-closing passage in said
case is formed as a passage having a circular section communicating
between said inlet and said outlet.
14. An intake control device of an internal combustion engine as
claimed in claim 13, wherein said valve body is a disk valve
inserted in said passage having the circular section.
15. An intake control device of an internal combustion engine
including an intake control valve mounted in an intake air passage
of said internal combustion engine and driven in timed relation
with rotation of said internal combustion engine to open and close
said intake air passage, and an intake manifold having said intake
air passage formed inside and a mounting bore communicating with
the upstream and downstream sides of said intake air passage; said
intake control valve comprising:
a case inserted in said mounting bore and having an inlet and an
outlet communicating with said upstream and downstream sides of
said intake air passage in said mounting bore and having an
opening-closing passage connecting said inlet to said outlet;
a valve body rotatably mounted in said case and opening and closing
said opening-closing passage;
driving means for rotating said valve body, said driving means
being mounted to said case, which will be inserted in said mounting
bore after said case, said valve body and said driving means are
assembled into one unit; and
connecting means for connecting said case to said driving means
relatively movably within a specific range of angle.
16. An intake control device of an internal combustion engine as
claimed in claim 15, wherein said airtight means is provided
between said case and said mounting bore to keep airtightness
between said upstream and downstream sides of said intake air
passage.
17. An intake control device of an internal combustion engine as
claimed in claim 15, wherein said inlet and said outlet of said
case are provided with chambers expanding toward said intake air
passage.
18. An intake control device of an internal combustion engine as
claimed in claim 15, wherein said opening-closing passage in said
case is formed as a passage having a circular section communicating
between said inlet and said outlet.
19. An intake control device of an internal combustion engine as
claimed in claim 18, wherein said valve body is a disk valve
inserted in said passage having the circular section.
20. An intake control device of an internal combustion engine
including an intake control valve mounted in an intake air passage
of said internal combustion engine and driven in timed relation
with rotation of said internal combustion engine to open and close
said intake air passage, and an intake manifold having said intake
air passage formed inside and a mounting bore communicating with
the upstream and downstream sides of said intake air passage; said
intake control valve comprising:
a case inserted in said mounting bore and having an inlet and an
outlet communicating with said upstream and downstream sides of
said intake air passage in said mounting bore and having an
opening-closing passage connecting said inlet to said outlet;
a valve body rotatably mounted in said case and opening and closing
said opening-closing passage; and
driving means for rotating said valve body,
said case being formed movably in a direction of said intake air
passage within said mounting bore, and mounted in said intake air
passage by connecting either one of said inlet side of said intake
air passage communicating with said mounting bore to an inlet
formed in said case and said outlet side of said intake air passage
communicating with said mounting bore to an outlet formed in said
case.
21. An intake control device of an internal combustion engine as
claimed in claim 20, wherein said airtight means is provided
between said case and said mounting bore to keep airtightness
between said upstream and downstream sides of said intake air
passage.
22. An intake control device of an internal combustion engine as
claimed in claim 20, wherein said inlet and said outlet of said
case are provided with chambers expanding toward said intake air
passage.
23. An intake control device of an internal combustion engine as
claimed in claim 20, wherein said opening-closing passage in said
case is formed as a passage having a circular section communicating
between said inlet and said outlet.
24. An intake control device of an internal combustion engine as
claimed in claim 23, wherein said valve body is a disk valve
inserted in said passage having the circular section.
25. An intake control device of an internal combustion engine
including an intake control valve mounted in an intake air passage
of said internal combustion engine and driven in timed relation
with rotation of said internal combustion engine to open and close
said intake air passage, and an intake manifold having said intake
air passage formed inside and a mounting bore communicating with
the upstream and downstream sides of said intake air passage; said
intake control valve comprising:
a case inserted in said mounting bore and having an inlet and an
outlet communicating with said upstream and downstream sides of
said intake air passage in said mounting bore and having an
opening-closing passage connecting said inlet to said outlet;
a valve body rotatably mounted in said case and opening and closing
said opening-closing passage; and
driving means for rotating said valve body,
said inlet or outlet of said case being provided with a heat
dissipating section for heat dissipation to an air stream flowing
in said intake air passage.
26. An intake control device of an internal combustion engine as
claimed in claim 25, wherein said airtight means is provided
between said case and said mounting bore to keep airtightness
between said upstream and downstream sides of said intake air
passage.
27. An intake control device of an internal combustion engine as
claimed in claim 25, wherein said inlet and said outlet of said
case are provided with chambers expanding toward said intake air
passage.
28. An intake control device of an internal combustion engine as
claimed in claim 25, wherein said opening-closing passage in said
case is formed as a passage having a circular section communicating
between said inlet and said outlet.
29. An intake control device of an internal combustion engine as
claimed in claim 28, wherein said valve body is a disk valve
inserted in said passage having the circular section.
30. An intake control device of an internal combustion engine
including an intake control valve mounted in an intake air passage
of said internal combustion engine and driven in timed relation
with rotation of said internal combustion engine to open and close
said intake air passage, and an intake manifold having said intake
air passage formed inside and a mounting bore communicating with
the upstream and downstream sides of said intake air passage; said
intake control valve comprising:
a case inserted in said mounting bore and having an inlet and an
outlet communicating with said upstream and downstream sides of
said intake air passage in said mounting bore and having an
opening-closing passage connecting said inlet to said outlet;
a valve body rotatably mounted in said case and opening and closing
said opening-closing passage;
driving means for rotating said valve body; and
a power transmission mechanism for transmitting a driving power,
between a support shaft for supporting said valve body and said
driving means.
31. An intake control device of an internal combustion engine as
claimed in claim 30, wherein said airtight means is provided
between said case and said mounting bore to keep airtightness
between said upstream and downstream sides of said intake air
passage.
32. An intake control device of an internal combustion engine as
claimed in claim 30, wherein said inlet and said outlet of said
case are provided with chambers expanding toward said intake air
passage.
33. An intake control device of an internal combustion engine as
claimed in claim 30, wherein said opening-closing passage in said
case is formed as a passage having a circular section communicating
between said inlet and said outlet.
34. An intake control device of an internal combustion engine as
claimed in claim 33, wherein said valve body is a disk valve
inserted in said passage having the circular section.
35. An intake control device of an internal combustion engine
including an intake control valve mounted in an intake air passage
of said internal combustion engine and driven in timed relation
with rotation of said internal combustion engine to open and close
said intake air passage, and an intake manifold having said intake
air passage formed inside and a mounting bore communicating with
the upstream and downstream sides of said intake air passage; said
intake control valve comprising:
a case inserted in said mounting bore and having an inlet and an
outlet communicating with said upstream and downstream sides of
said intake air passage in said mounting bore and having an
opening-closing passage connecting said inlet to said outlet;
a valve body rotatably mounted in said case and opening and closing
said opening-closing passage; and
driving means for rotating said valve body,
said driving means being an electric driving means for driving said
valve body in accordance with an electric signal, maintaining said
valve body partly opened when no current is supplied, and for
driving said valve body in a fully opening and fully closing
direction in accordance with the direction of current supply.
36. An intake control device of an internal combustion engine as
claimed in claim 35, wherein said airtight means is provided
between said case and said mounting bore to keep airtightness
between said upstream and downstream sides of said intake air
passage.
37. An intake control device of an internal combustion engine as
claimed in claim 35, wherein said inlet and said outlet of said
case are provided with chambers expanding toward said intake air
passage.
38. An intake control device of an internal combustion engine as
claimed in claim 35, wherein said opening-closing passage in said
case is formed as a passage having a circular section communicating
between said inlet and said outlet.
39. An intake control device of an internal combustion engine as
claimed in claim 38, wherein said valve body is a disk valve
inserted in said passage having the circular section.
40. An intake control device of an internal combustion engine,
comprising:
an intake manifold connected to said internal combustion engine and
having an intake air passage through which the intake air passes
into said internal combustion engine;
a throttle valve mounted upstream of said intake manifold and
driven to open and close in accordance with a demand for
controlling the rotational speed of said internal combustion
engine;
a mounting bore formed in said intake manifold and communicating
with the upstream and downstream sides of said intake air passage
located at the downstream of said throttle valve, opening
outwardly;
a case inserted in said mounting bore, provided with an inlet and
an outlet communicating with the upstream side and downstream side
of said intake passage in said mounting bore, and having an
opening-closing passage connecting said inlet to said outlet;
a valve body rotatably mounted in said case, for opening and
closing said opening-closing passage; and
driving means connected to said and driving said valve body in
order to change the opening of said openingclosing passage
synchronously with the rotation of said internal combustion
engine,
said intake control valve being driven in timed relation with the
operation of an intake valve mounted at the inlet of a combustion
chamber of said internal combustion engine, controlling, by each
intake stroke, the amount of intake air being supplied into said
combustion chamber of said internal combustion engine.
41. An intake control valve used in an intake control device of an
internal combustion engine for controlling the amount of intake air
being supplied through an intake air passage into a combustion
chamber of said internal combustion engine in timed relation with
the rotation of said internal combustion engine, said intake
control valve, comprising:
a case having an inlet communicating with the upstream side of said
passage, an outlet communicating with the downstream side of said
passage, and an opening-closing passage connecting said inlet to
said outlet, and inserted in a mounting bore formed in said
passage;
a valve body rotating within said case to change the opening of
said opening-closing passage; and
driving means installed to said case, connected to said valve body,
said intake control valve being drive in timed relation with the
operation of an intake valve mounted at the inlet of a combustion
chamber of said internal combustion engine, controlling, by each
intake stroke, the amount of intake air being supplied into said
combustion chamber of said internal combustion engine.
Description
DESCRIPTION
1. Technical Field
The present invention relates to an intake control device of an
internal combustion engine provided with an intake control valve in
each intake passage communicating with each engine cylinder and an
intake valve installed in a combustion chamber of the internal
combustion engine and, more particularly, to the constitution of
these intake control valves.
2. Background Art
In the internal combustion engine, there sometimes takes place a
state of valve overlap in which an intake valve and an exhaust
valve simultaneously open when the intake stroke starts. In such a
case there occurs the back flow of burned gases from inside the
cylinder and an exhaust passage into an intake passage, resulting
in such a trouble as a lowered intake air charging efficiency and
deteriorated fuel economy. To prevent this back flow of burned
gases by means of an intake control valve, there has been proposed,
as disclosed in for example Japanese Patent Laid-Open No. Sho
63-65138, a means to prevent the back flow by the intake control
valve installed in each intake passage communicating with each
engine cylinder and an intake valve is provided in the combustion
chamber of the internal combustion engine. On the valve overlap
when the intake and exhaust valves are simultaneously opened, each
of these intake control valves is operated by an independent
actuator to close the intake air passage, thereby checking the back
flow of the burned gases to improve the intake air charging
efficiency.
Since the quantity of intake air to be drawn into the combustion
chamber of the internal combustion engine can be controlled by
controlling an air intake period by the intake control valve
simultaneously with the movement of an internal engine piston, it
is possible to open the throttle valve wide to maintain a high
intake passage pressure on the intake stroke. Therefore, air supply
into the internal combustion engine during partial load operation
can easily be performed, thereby reducing a pumping loss, realizing
an increase in an internal engine torque and improving fuel
economy.
However, the prior-art intake control valve disclosed in the
aforementioned patent publication is of such a structure that a
push rod is actuated by an actuator which includes a piezoelectric
element disposed outside of the intake passage, to thereby operate
a valve body which comprises a plurality of spring plate members
installed in the intake passage, thus opening and closing the
intake passage.
The aforesaid intake control valve has many component parts because
the valve body thereof uses a number of plate members to open and
close the intake passage and requires much time to install. In
addition a clearance is likely to occur between each valve body and
the intake passage, giving a considerable influence to the engine
performance. To eliminate this clearance, it will become necessary
to improve a valve body processing accuracy, which, however, will
result in an increased cost.
Furthermore, the prior-art intake control device has the following
disadvantage that the overall structure of the intake control valve
including the actuator consisting of the piezoelectric element and
others is likely to become large in size and further the
surrounding structure of the intake passage becomes complicated,
and also it has so excessive weight as to give a great effect to
the weight of the vehicle body, thus increasing the fuel
consumption of the internal combustion engine.
DISCLOSURE OF THE INVENTION
The present invention has been accomplished in an attempt to
obviate the above-mentioned disadvantages and has as its object the
provision of an intake control device of an internal combustion
engine which is easy to handle and can easily be mounted in the
intake air passage.
It is another object of the present invention to improve the
clearance accuracy of the intake control device and to control
intake operation with high accuracy by reducing air leakage.
It is further another object of the present invention to provide an
intake control valve which is small in size and light in weight and
can easily be installed in the intake air passage.
In an attempt to accomplish the above object, the present invention
adopts the following constitution.
In the intake control device of an internal combustion engine
having the intake control valve which is mounted in the intake air
passage of the internal combustion engine and operated to open and
close the intake air passage simultaneously with the rotation of
the internal combustion engine, the present invention provides:
an intake manifold with the intake air passage formed therein and a
mounting bore formed communicating with the upstream and downstream
sides of the intake passage; and
the intake control valve, which includes
a case which is inserted in the mounting bore, has an inlet and an
outlet communicating with the upstream and downstream sides
respectively of the intake air passage in the mounting bore, and
has an opening-closing passage connected to the inlet and
outlet,
a valve body which is rotatably mounted in this case to open and
close the opening-closing passage,
a driving means which drives to rotate the valve body.
Also the present invention provides an intake control device of
internal combustion engine comprising:
an intake manifold which is connected to the internal combustion
engine and has the intake air passage through which the intake air
passes into the internal combustion engine;
a throttle valve installed on the upstream side of the intake
manifold and driven to open and close in accordance with a demand
for controlling the speed of rotation of the internal combustion
engine;
a mounting bore formed in the intake manifold and opening
outwardly, communicating with the upstream and downstream sides of
the intake air passage located at the downstream of the throttle
valve;
a case inserted in the mounting bore, having an inlet and an outlet
communicating with the upstream and downstream sides of the intake
passage in the mounting bore, and having an opening-closing passage
connecting the inlet and outlet to each other;
a valve body rotatably mounted in this case, and opening and
closing the opening-closing passage; and
a driving means connected to the case, and driving the valve body
to change the amount of opening of the opening-closing passage
simultaneously with the rotation of the internal combustion
engine.
Also, in the intake control device of the internal combustion
engine for controlling the quantity of intake air to be supplied to
combustion chambers of the internal combustion engine
simultaneously with the rotation of the engine, the present
invention provides an intake control valve comprising:
a case having an inlet communicating with the upstream side of the
intake air passage, an outlet communicating with the downstream
side of the passage, and an opening-closing passage communicating
with the inlet and outlet, and being inserted in the mounting bore
formed in the passage;
a valve body rotating in the case to change the opening of the
opening-closing passage; and
a driving means installed to the case and connected to the valve
body, and driving to rotate the valve body simultaneously with the
rotation of the internal combustion engine.
According to the constitution of the brake control device of the
present invention, the intake air passage is formed in the intake
manifold, in which the mounting bore is formed. In the meantime,
the intake control valve which is driven to open and close
simultaneously with the rotation of the internal combustion engine
includes the case, the valve body housed in this case, and the
driving means for driving this valve body. In the case are formed
the inlet and outlet communicating with the upstream and downstream
sides of the intake air passage respectively, and further the
opening-closing passage is formed to communicate with the inlet and
outlet. The valve body is housed within the case so as to open and
close the opening-closing passage in the case. The intake control
valve is installed in the intake air passage by inserting this case
in the mounting bore. With the operation of the valve body driven
by the driving means, the opening-closing passage is opened and
closed, thereby controlling the quantity of intake air flowing
within this opening-closing passage. The brake control device of
the present invention is so constituted that the case for holding
the valve body is inserted in the mounting bore formed in the
intake manifold, to thereby open and close the intake air passage.
Therefore, the intake manifold of a simple constitution having only
the mounting bore can be made. In addition since the intake control
valve can be installed simply by inserting the case in the mounting
bore, the handling, manufacture and assembly of the device can all
be accomplished with ease.
Also, according to the constitution of the present invention, the
intake control valve of the intake control device is mounted in the
intake manifold downstream of the throttle valve; the amount of
opening of the opening-closing passage is changed by driving the
valve body simultaneously with the rotation of the internal
combustion engine.
Furthermore, according to the present invention, the intake control
valve of the intake control device is of such a constitution that
the valve body, the case and the driving means make an assembly
wherein the valve body is installed in the case, and the driving
means is installed to the case; therefore the intake control valve
can be connected to the intake air passage simply by inserting this
case as an assembly into the mounting bore.
According to the present invention explained above, the intake
control valve can be installed in the intake air passage merely by
installing the valve body in the case and then by inserting the
case in the mounting bore formed in the intake manifold, thereby
enabling the provision of the intake control device having the
intake control valve which assures the simplification of the
constitution of the intake manifold, easy handling of the device,
and easy mounting of the device in the intake air passage.
Furthermore, according to the present invention, it is possible to
make high-accuracy control of the quantity of intake air by
decreasing intake air leakage through high-accuracy control of a
clearance between the valve body and the case.
Furthermore, the present invention can provide a small-sized,
light-weight, easy-to-handle intake control device which is
composed of the case, the valve body and the driving means all
assembled into an assembly and therefore is easily mountable in the
intake air passage.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded sectional view showing a first embodiment of
the present invention in which an intake control valve unit is
mounted in an intake manifold;
FIG. 2 is a sectional view showing the state of the first
embodiment of the intake control unit mounted in the intake
manifold;
FIG. 3 is a side view showing the first embodiment of the intake
control valve unit exploded into a case and an actuator;
FIG. 4 is a front view of the case taken in the direction of the
arrow A of FIG. 3;
FIG. 5 is a plan view of the case taken along line 5--5 of FIG.
3;
FIG. 6 is a plan view of the actuator taken along line 7--7 of FIG.
3;
FIG. 7 is a sectional view taken along line 7--7 of FIG. 3;
FIG. 8 is a sectional view taken along line 8--8 of FIG. 2;
FIG. 9 is a block diagram showing the first embodiment of the
intake control system in a four-cylinder engine;
FIG. 10 is a plan view of a second embodiment of the case according
to the present invention;
FIG. 11 is a plan view of the second embodiment of the
actuator;
FIG. 12 is a sectional view showing a third embodiment of the
present invention, in which the case is installed to the intake
manifold;
FIGS. 13(a) and 13(b) show a fourth embodiment of the present
invention, in which FIG. 13(a) is a front view of the case and FIG.
13(b) is a side view of the case;
FIGS. 14(a) and 14(b) show a fifth embodiment of the present
invention, in which FIG. 14(a) is a front view of the case and FIG.
14(b) is a side view of the case;
FIGS. 15(a) and 15(b) show a sixth embodiment of the present
invention, in which FIG. 15(a) is a front view of the case and FIG.
15(b) is a side view of the case;
FIGS. 16(a) and 16(b) show a seventh embodiment of the present
invention, in which FIG. 16(a) is a front view of the case and FIG.
16(b) is a side view of the case;
FIGS. 17(a) and 17(b) show an eighth embodiment of the present
invention, in which FIG. 17(a) is a front view of the case and FIG.
17(b) is a side view of the case;
FIGS. 18(a) and 18(b) show a ninth embodiment of the present
invention, in which FIG. 18(a) is a front view of the case and FIG.
18(b) is a side view of the case;
FIGS. 19(a) and 19(b) show a tenth embodiment of the present
invention, in which FIG. 19(a) is a front view of the case and FIG.
19(b) is a side view of the case;
FIGS. 20(a) and 20(b) show a eleventh embodiment of the present
invention, in which FIG. 20(a) is a front view of the case and FIG.
20(b) is a side view of the case;
FIG. 21 is an exploded perspective view showing a twelfth
embodiment of the present invention, in which the intake control
valve unit is mounted in the intake manifold;
FIG. 22 is a plan view showing the case of the twelfth
embodiment;
FIG. 23 is a partially sectional view showing a thirteenth
embodiment of the present invention, in which the case is mounted
in the intake manifold;
FIG. 24 is a partially sectional view showing a fourteenth
embodiment of the present invention, in which the case is mounted
in the intake manifold;
FIG. 25 is a front view of the case showing a fifteenth embodiment
of the present invention;
FIG. 26 is a front view showing the positional relationship of the
case and the actuator according to a sixteenth embodiment of the
present invention;
FIG. 27 is a partially sectional view showing the constitution of
the case and the valve body according to a seventeenth embodiment
of the present invention;
FIGS. 28, 29 and 30 are time charts explaining examples of
operation of the intake control valve; and
FIGS. 31 and 32 are tables showing the valve opening timing and
valve closing timing of the intake control valve of the first
embodiment.
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter the first embodiment of the brake control device of
internal combustion engine according to the present invention will
be explained with reference to the accompanying drawings 1 to
9.
FIG. 9 is a block diagram showing an intake control system of a
four-cylinder engine 1. To each cylinder 2 of the engine 1 are
connected an intake air passage 4 branched off from an intake
manifold 3 and an exhaust passage 6 branched off from an exhaust
manifold 5. In the intake manifold 3 is provided a throttle valve
3a which is opened and closed in accordance with the amount of
operation of an accelerator pedal by a driver. There is set a
specific operating characteristic between the amount of operation
of the accelerator pedal and the amount of opening of the throttle
valve 3a. The opening of the throttle valve 3a is controlled in
accordance with this characteristic.
In the combustion chamber of each cylinder 2 are set an intake
valve 7 which opens and closes the intake air passage 4 and an
exhaust valve 8 which opens and closes the exhaust gas passage
6.
In each intake air passage 4 which is branched off from the intake
manifold is installed an intake control valve 10.
The intake control valve 10 is operated to open and close
independently of the opening and closing of the intake valve 7 in
accordance with a signal of electric supply from the input-output
section 12 of the control circuit 11. The control circuit 11 has a
computer (CPU) 13, a read-only memory (ROM) 14 used for the storage
of control programs, and a random-access memory (RAM) 15 used for
the storage of control data, which are all built in the control
circuit 11.
Connected to this control circuit 11 are a plurality of detectors
16. A crank angle sensor 16a is designed to produce a pulse signal
when a piston (not illustrated) in each cylinder 2 is positioned at
top dead center (TDC). A rotational speed sensor 16b produces a
pulse signal at every specific crank angle. An intake air quantity
detecting means 16c including a pressure sensor in the intake pipe
functions to detect the quantity of intake air by each cylinder.
Furthermore, a load detecting means 16d including a throttle
opening sensor, an accelerator operating stroke sensor functions to
detect the loaded condition of the engine.
The detection signal from each of the sensors 16a to 16d is
inputted to the computer 13 through the input-output section 12 of
the control circuit 11. This computer 13 controls the engine 1
through the input-output section 12 and at the same time gives off
a control signal to the opening-closing driving means, that is, the
actuator, of the intake control valve 10.
The intake control valve 10 is particularly shown in FIGS. 1 to 8,
which will be explained below.
In the drawings, a numeral 20 refers to a case which will become
the body of the intake control valve 10 manufactured, for example,
of aluminum or aluminum alloy. This case 20 is of a cylindrical
form with a closed top side, and has an inlet 21 and an outlet 22
in side walls which are open in opposite positions. Between the
inlet 21 and the outlet 22 is formed an opening-closing passage 23
of the same size and same shape as the intake air passage 4. At the
bottom of the case 20 a flange section 24 is formed and an
inserting bore 25 communicating with the opening-closing passage 23
is open. In the top side of the case 20 is formed a bearing housing
recess 26.
In the outside surface of the case 20 are provided packing fitting
grooves of a square form when viewed from the inlet or outlet side,
surrounding the inlet 21 and the outlet 22. Fitted in these grooves
are ring-shaped rubber packings 27 and 28 round in section as
sealing members.
Within this case 20 is rotatably installed a valve body 30, which
is a cylindrical valve formed by adding an upper disk 35 and a
lower disk 36 on and under a butterfly valve produced of aluminum
or aluminum alloy, and coated with Teflon on the outside
surface.
The valve body 30 is pressed over a pivot 31 inserted from the
inserting bore 25 into the opening-closing passage 23, and is
designed to rotate within the case 20 with the rotation of the
pivot 31. With the rotation of the pivot 31 the valve body 30 is
turned to each position shown in FIG. 8, thereby controlling the
opening of the opening-closing passage 23. There is a very little
clearance provided between the valve body 30 and the inner wall of
the opening-closing passage 23, so that the valve body 30 rotates
without contacting the opening-closing passage 23.
The pivot 31 is rotatably supported at the top end on a bearing 32,
which is fitted in the aforesaid bearing housing recess 26 formed
in the top side of the case 20.
The lower end of this pivot 31 extends into an opening-closing
driving means, that is, an actuator 40, and is driven to turn by
this actuator 40.
The actuator 40 has a flange 42 at the top end of the cylindrical
housing 41; into the interior of this housing 41 the lower end of
the pivot 31 extends. On the pivot 31 is installed a rotary magnet
42, which, as shown in FIG. 7, is a cylindrical type and located in
the actuator housing 41. The rotary magnet 42 has been magnetized
so that its magnetic poles will vary in circumferential symmetrical
positions. On the inner wall of the actuator housing 41 are
installed a pair of magnetic coils 43a and 43b and a pair of
permanent magnets 44a and 44b. These magnetic coils 43a and 43b and
the permanent magnets 44a and 44b are arranged in mutually
rectangular positions to control the rotational position of the
rotary magnet 42 in accordance with the amount of magnetic force of
these magnets.
That is, when the current is supplied to excite for example the
magnetic coils 43a and 43b to the positive side, the rotary magnet
42 turns to a position determined by the magnetic pole formed by
these magnetic coils 43a and 43b and the magnetic pole formed by
the permanent magnets 44a and 44b, and accordingly the cylindrical
valve body 30 turns to a full-open position indicated by an
alternate long and short dash line in FIG. 8.
Also when the current is supplied to excite the magnetic coils 43a
and 43b to the negative side, the rotary magnet 42 turns to a
position determined by the magnetic pole formed by these magnetic
coils 43a and 43b and the magnetic pole formed by the permanent
magnets 44a and 44b, and accordingly the valve body 30 turns to a
full-close position indicated by a full line in FIG. 9.
Furthermore, when the current supply to the magnetic coils 43a and
43b is interrupted, the rotary magnet 42 is turned by the magnetic
pole formed by only the permanent magnets 44a and 44b, thus turning
the valve body 30 to a half-open position indicated by a broken
like in FIG. 8. In this half-open position, an air flow path is
provided between the valve body 30 and the inner surface of the
opening-closing passage 23.
To the cylindrical housing 41 of the actuator 40 is connected the
case 20, and the valve body 30 and the actuator 40 are integrally
installed also to the case 20, thereby unitizing the intake control
valve 10.
On the flange section 24 of the case 20 are formed a pair of screw
holes 29 on a diagonal line and a pair of through-holes 45 on the
other diagonal line as shown in FIG. 5. In the flange section 42
formed in the cylindrical housing 41 of the actuator 40 are formed
through-holes 46 in four corners as shown in FIG. 6. These flange
sections 24 and 42 are connected to each other by inserting small
screws 47 (see FIG. 1 or 3) from the flange section 42 side of the
housing 41 into the pair of through-holes 46 located at diagonal
positions, and then tightening them into the pair of screw holes 29
formed in the flange section 24 of the case 20. In the remaining
through-hole 46 provided in the flange section 42 of the housing 41
and in the through-hole 46 in the flange section 24 of the case 20
are inserted bolts 48 from the flange section 42 side of the
housing 41 as explained later on. The intake control valve 10 is
mounted to the intake air passage 4 by the bolts 48.
The intake control valve 10 is utilized by connecting these flange
sections 24 and 42. This unitized intake control valve 10 is
installed to the intake air passage 4 communicating with the
cylinder 2 of the engine 1.
The intake air passage 4 in which the intake control valve 10 is
inserted is formed in an intake manifold 50 produced for example of
aluminum or aluminum alloy. In the side wall of this intake
manifold 50 is a mounting bore 51 for mounting the intake control
valve 10. In the inner surface of the intake air passage 4 opposite
to this mounting bore 51 is formed a fitting recess section 52 in
which the top section of the case 20 of the intake control valve 10
fits.
The case 20 of the intake control valve 10 is inserted into the
intake manifold 50 through the mounting bore 51, and the top
section of the case 20 is fitted into the fitting recess 52. Then,
the inlet 21 formed in the case 20 is directed to the upstream side
of the intake air passage 4, while the outlet 22 placed oppositely
to the downstream side; in this state the intake control valve 10
is fastened by bolts 48 to the intake manifold 50.
In this case, the bolts 48 are screwed into screw holes in the
intake manifold 50 after inserting through the pair of
through-holes 46 and the through-holes 45 provided in the flange
section 24 of the case 20 from below the flange section 42 of the
actuator 40, thus installing the intake control valve 10 to the
intake manifold 50.
In the mounted state of the intake control valve 10, the rubber
packings 27 and 28 installed in the outer side surfaces of the case
20, surrounding the inlet 21 and the outlet 22, are pressed in
contact with the intake manifold 50 to thereby keep airtightness
between the intake manifold 50 and the intake control valve 10.
Next, the function of the present embodiment of the above-described
constitution will be explained.
The intake control valve 10 is driven simultaneously with the
rotation of the internal combustion engine to control the quantity
of intake air to be supplied to the combustion chamber of the
internal combustion engine by each cylinder and by each intake
stroke.
In the present embodiment, the valve opening timing and the valve
closing timing of each intake control valve are separately set to
control the opening and closing of each intake control valve.
First, the valve opening timing TO of the intake control valve is
determined in accordance with FIG. 31. This valve opening timing TO
is indicated in terms of the advance angle to top dead center on
the intake stroke.
Subsequently the valve closing timing TC of the intake control
valve is determined by the equation given below. The valve closing
timing TC is indicated in terms of the advance angle to bottom dead
center (BDC) on the intake stroke.
where TC is the valve closing timing; TCBSE is the amount of basic
valve closing advance angle, which are obtained from FIG. 32; TTC
is the mount of transient A/F compensating advance angle, or the
amount of compensation for controlling the air-fuel ratio to a
desired ratio at the time of transient change in the engine speed;
FTC is the amount of combustion temperature compensating advance
angle, which is set to control the combustion temperature to a
desired value; TRTC is the amount of traction control compensating
advance angle, which is set for respective high-accuracy control of
the amount of air supply to the cylinders at the time of traction
control for preventing a driving wheel slip during vehicle
acceleration from standstill; BTC is the amount of intake air brake
control compensating advance angle at the time of deceleration,
which is set to improve the effect of engine brake during
deceleration; NTC is the amount of compensating advance angle at
the time when engine knocks are occurring, which is set to reduce
the knocks when the knocks take place; NETC is the amount of air
supply control compensating advance angle, which is set to control
the amount of intake air by each cylinder to a specific value; and
TDC is the amount of time variation compensating advance angle of
the actuator, which is set to prevent controllability deterioration
by a change in responsibility and a change in valve opening likely
to be caused by the time variation of the actuator. The amount of
basic valve closing advance angle TCBSE is set on the basis of an
engine speed and a loaded condition of the engine in FIG. 32. The
loaded condition of the engine is determined from the depth of
depression of the accelerator pedal, etc. In FIG. 32, a partial
load range within which the engine load is relatively little is
divided to a large and a small range, and further a full-load
condition is added, so that the amount of basic valve closing
advance angle will be set by each speed in each of these three load
ranges.
The valve opening timing TO and valve closing timing TC of each
intake control valve are set as described above, and a valve
driving current is supplied from the control device to the intake
control valve in accordance with these valve opening timing TO and
valve closing timing TC.
Therefore, each intake control valve is opened and closed
simultaneously with the intake operation of each cylinder of the
engine, and the intake timing and the amount of intake air supplied
to each cylinder of the engine are controlled by the intake stroke
of the cylinder.
In setting the valve opening timing also, a specific calculation
formula is set similarly as the setting of the valve closing timing
described above, and then the valve opening timing may be set on
the basis of various amounts of compensation.
According to the intake control valve 10 of the present embodiment,
the case 20, the valve body 30 and the actuator 40 are assembled in
one unit, and therefore the intake control valve 10 becomes easy to
handle; in particular, the intake control valve 10 can easily be
installed in the intake air passage 4 simply by inserting the case
20 into the mounting bore 51 of the intake manifold 50.
Furthermore since the intake control valve 10 of the present
embodiment thus unitized has the rotary valve body 30 for opening
and closing the opening-closing passage 23 in the case 20 which is
provided with the inlet 21 and the outlet 22, only one valve body
is sufficient; besides since it is a rotary type, the intake
control valve 10 is simple in construction with a decreased number
of component parts, and the actuator 40 as an opening-closing
driving means becomes of a simple construction.
In executing the intake control, the clearance of the intake
control valve 10 which has an effect on intake air leakage is
required to have a strictly high accuracy. However, the intake
control valve 10 of the above-described constitution is of such a
construction that the rotary valve body 30 is enclosed with the
case 20, and therefore there can be kept a high-accuracy clearance
between the case 20 and the valve body 30 simply by controlling the
material, working accuracy and surface finish of these parts.
Particularly, there is the effect that the intake control valve 10
will not be affected by the working accuracy of the intake manifold
50 which is a casting. In addition, the performance inspection and
control of the intake control valve unit alone can be performed
prior to the installation of the valve unit in the intake manifold
50, and because only a quality product is adopted, a greater yield
than the valve of conventional constitution can be substantially
improved.
When the valve body 30 is installed directly in the intake manifold
50 without using the case 20, there will be a wide clearance
between the intake manifold and the valve body because the intake
manifold produced of aluminum has a large casting variation which
makes it difficult to perform inside surface machining and surface
treatment; therefore if the aluminum valve body is coated with a
Teflon resin, it is impossible to obtain a 50 .mu. or less
clearance due to a large thermal change in the clearance resulting
from a difference in the coefficient of thermal expansion between
the aluminum and the Teflon resin.
On the other hand, as in the present embodiment, the thermal
expansion characteristics of the valve body 30 and the case 30 can
be approximated by mounting the intake control valve 10 of the unit
construction that has the case 20 with the valve body 30 installed
in the case 20, thus facilitating improving the working accuracy of
the valve body 30 and the case 20 and the surface treatment such as
surface coating and oxidation treatment and accordingly realizing
the provision of an approximately 10 .mu.m clearance.
Also, since the case is separate from the intake manifold 50, the
inner surface of the case 20 and the opening-closing passage 23 can
be mirror-finished, thereby further improving a clearance accuracy
and preventing attachment of deposits.
Furthermore, the unitized intake control valve 10 can not only
diminish a separate clearance but, in the state that the intake
control valve 10 is installed in the intake manifold 50, the rubber
packings 27 and 28 surrounding the inlet 21 and the outlet 22 are
being pressed against the intake manifold 50 and therefore there is
maintained a high-accuracy airtightness between the intake manifold
50 and the intake control valve 10 unit, thence giving no adverse
effect to the clearance between the intake manifold 50 and the
intake control valve 10.
In this case, since the rubber packings are employed, machining a
bore in the intake manifold 50 requires no high accuracy and
therefore the intake manifold 50 is applicable to various types of
engines.
Furthermore, the coefficient of thermal expansion of the case 20
can easily be matched to that of the intake manifold 50, thus
effectively reducing the clearance.
According to the constitution of the brake control device of the
present embodiment, intake air leakage can be decreased by
improving the accuracy of the case-to-intake manifold clearance and
further by installing the rubber packings between the case and the
intake manifold; therefore high-accuracy control can be effected
when fine intake air control is required particularly during
partial load operation and low-speed operation.
Since the intake control valve 10 of the above-described
constitution is of such a construction that the rotary valve body
30 is enclosed with the case 20 and the actuator 40 is connected
thereto, it is possible to realize a small-size, light-weight valve
of simple construction.
In the case of the present embodiment, the use of a small-sized
case 20 with the valve body 30 covered in one unit is usable, and
its thermal capacity can be reduced to a less value as compared
with the intake manifold. Therefore the thermal capacity of the
case 20 can be made approximately equal to the thermal capacity of
the valve body 30. Also since the case 20 is in contact with the
intake air similarly to the valve body 30, heat dissipation to the
case 20 and the valve body 30 can be made nearly equal. Furthermore
the thermal capacities of the case 20 and the valve body 30 can be
made nearly equal and a time difference of thermal deformation and
change of the case 20 and the valve body 30 can be minimized.
Consequently, the case 20 and the valve body 30 are subjected to
shrinkage and expansion at an approximately same rate at the time
of a sudden change in intake temperature, and accordingly a large
change in a clearance between the both parts can be prevented.
Particularly the internal combustion engine sometimes uses an
exhaust gas recirculation (EGR) system to reduce NOx in exhaust
gases. When the EGR is used, hot exhaust gases flow into the intake
control valve 10; according to the above-described constitution, it
is possible to prevent the occurrence of a heat trouble caused by
the inflow of the hot gases from the EGR.
Next, the second embodiment of the present invention will be
explained by referring to FIGS. 10 and 11.
In the second embodiment, the case 20 has long circular holes 90 in
four corners of the flange section 24 as shown in FIG. 10. On the
other hand, the actuator 40 has a pair of screw holes 92 and a pair
of through-holes 93 in diagonal positions in the flange section 42
formed in the cylindrical housing 41 as shown in FIG. 11. These
flange sections 24 and 42 are connected to each other by inserting
countersunk head screws 95 into the pair of long holes 90 provided
in diagonal positions, from the flange section 24 side of the case
20, and then by screwing these countersunk head screws 95 into the
screw holes 92 formed in the flange section 42 of the housing 41.
In this case, the countersunk head screws 95 are installed with
their heads below the top surface of the flange section 24 of the
case 20. Subsequently the bolts 48 are inserted into the pair of
through-holes 93 from below the flange section 42 of the actuator
40, and also into the long holes provided in the flange section 24
of the case 20, and then are screwed into the screw holes in the
intake manifold 50, thus mounting the intake control valve 10 to
the intake manifold 50.
In the case of the second embodiment, the case 20 of the intake
control valve 10, being attached to the actuator 40 by the use of
the countersunk head screws 95 inserted in the long holes 90, is
rotatable with respect to the actuator 40; the case 20 and the
valve body 30, therefore, make relative rotation to adjust their
positions. These positions can be fine-adjusted if the valve body
30 fails to properly operate in the full-open and full-close
positions because of an unbalanced magnetic force of the actuator
40.
Since the case 20 is attached in the intake manifold 50 by the
bolts 49 inserted in a remaining pair of long holes 90 provided in
the flange section 24, it is possible to adjust the position of the
case 20 relative to the intake manifold 50 by turning the case 20,
and also to make the high-accuracy positional adjustment with the
inlet 21 and the outlet 22 directed to the upstream and downstream
sides of the intake passage 4.
Next, the third embodiment of the present invention will be
explained by referring to FIG. 12.
In the third embodiment, the inlet 21 and the outlet 22 of the case
20 are provided with chambers 21a and 22a at their opening as shown
in FIG. 12. When mounting the unit of the intake control valve 10
in the intake manifold 50, there sometimes occurs a positional
misalignment, and accordingly a step, as indicated by a broken line
in FIG. 12 between the intake air passage 4 and the inlet 21 and
outlet 22 of the case 20 because of the presence of forming
variation of the intake air passage 4 and working variation of the
fitting recess 52. In the case of such a mounting condition, the
surface of the intake air passage suddenly changes, giving an
adverse effect to the intake characteristics. However, the sudden
change in the surface area of the intake air passage due to the
presence of the step can be prevented by providing the chambers 21a
and 22a on the opening of either of the inlet 21 and the outlet
22.
Next, the fourth to fourteenth embodiments showing variations of
constitution of the brake control device for keeping airtightness
between the case and the intake manifold will be explained.
In the first embodiment, the sealing members comprising the rubber
packings 27 and 28 are used in the outer surface of the case 20 for
the purpose of keeping airtightness between the case 20 and the
intake manifold 50; these rubber packings can be effected in
various embodiments shown in FIGS. 13 to 20. That is, in FIGS.
13(a) to 20(a), the view is a front view of the case 20 as viewed
from the inlet side, while in FIGS. 13(b) to 20(b) the view is a
side view of the case 20. A reference numeral 60 in these drawings
refers to a sealing member comprising a rubber packing.
In the aforementioned embodiments shown in FIGS. 13(a) and (b),
16(a) and (b), 17(a) and (b), 18(a) and (b) and 19(a) and (b) there
is a fear that there occurs a blow-by of the intake air through
between the case 20 and the mounting bore 51 of the intake manifold
50; therefore it is desirable to seal (not illustrated) the upper
surface 24a of the flange surface 24. It is imperative for this
airtight structure to prevent the flow of the intake air into the
internal combustion engine between the case and the intake
manifold. Also, the sectional form of the rubber packing may have a
projecting part for thereby assuring high airtightness.
Next, the twelfth embodiment of the present invention will be
explained by referring to FIG. 21.
In the twelfth embodiment, airtightness is kept by parallelly
moving the intake control valve 10 as shown in FIG. 21. In this
embodiment, an inner surface 50a of the mounting bore of the intake
manifold 50 is made in a form of rectangular flat surface; a
contact surface 20a of the case 20 which is in contact with this
inner surface 50a is also made in a form of rectangular flat
surface. Furthermore, a long hole 90a in the flange section 24 of
the case 20 is formed long in the direction of the upstream and
downstream sides of the intake air passage 4 as shown in FIG. 22.
After the case 20 unit of the intake control valve 10 is inserted
in the mounting bore, the case 20 is moved in the direction of the
arrow Y in FIG. 21 until the contact surface 20a of the case 20 is
in close contact with the inner surface 50a of the mounting bore to
securely install the intake control valve 10 to the intake manifold
50, thereby maintaining airtightness by holding the contact surface
20a in close contact with the inner surface 50a and the flange 24
in close contact with the intake manifold 50. The airtightness can
be further improved by coating a liquid such as an adhesive or an
oil over the contact surface.
Subsequently, the thirteenth embodiment of the present invention
will be explained by referring to FIG. 23.
In the present embodiment, the inner surfaces of the case 20 of the
intake control valve 10 and the mounting bore of the intake
manifold 50 are provided with chambers 70 and 71; and either one
(the case 20 in the drawing) of the case 20 of the intake control
valve 10 or the intake manifold 50 is provided with a projecting
part 72. The projecting part 72 is pressed close to the chamfer 71,
thereby closely contacting the chambers 70 and 71 with each other.
This constitution, therefore, has such an advantage that a
positional misalignment between the case 20 of the intake control
valve 10 and the intake air passage 4 of the intake manifold 50 can
be prevented.
Next, the fourteenth embodiment of the present invention will be
explained by referring to FIG. 24.
In the present embodiment, as shown in FIG. 24, a groove is made in
either one of the contact surface 20a of the case 20 and the inner
surface 50a of the intake manifold 50. In this groove is filled an
adhesive 80, pressing these contact surfaces against each
other.
Next, the fifteenth embodiment of the present invention will be
explained by referring to FIG. 25.
In the present embodiment, the projecting part 90 is formed at the
inlet 21 and the outlet 22 of the case 20 to insure positive heat
dissipation to the case 20. The position and width of the
projecting part 90 are so determined that it will overlap the valve
body 30 when the valve body 30 is in a full-open position; the heat
of the case 20 is dissipated to the intake air stream without
increasing resistance in relation to the intake air stream.
Next, the sixteenth embodiment of the present invention will be
explained by referring to FIG. 26.
In the present embodiment, the case 20 and the actuator 40 are
separately installed, and furthermore, with their axes intersecting
at right angles, a power transmission mechanism is provided. On the
end of the valve body support shaft 31b provided in the case 20 is
mounted a helical gear 31c, and on the end 31d of the actuator 40
is mounted a helical gear 31e. With these helical gears in mesh
with each other, the actuator 40 is connected to the valve body to
drive the valve body. In this embodiment, the case 20 is mounted in
the intake manifold, while the actuator 40 is secured to the engine
by a stay not illustrated. According to this embodiment, since the
case 20 installed at least to the intake manifold and the valve
body housed in the case 30 and driven to rotate are unitized, it is
possible to improve the accuracy of the intake control valve
installed in the intake air passage, and further to decrease the
clearance to reduce intake air leakage, thereby enabling
high-accuracy intake quantity control.
Next, the seventeenth embodiment of the present invention will be
explained by referring to FIG. 27.
In each of the above-described embodiments, the cylindrical valve
is used as the valve body 30, which, however, may be made in a form
of cylindrical valve. In FIG. 27 a disk-like valve body 30 is
housed in the case 20, and in this valve body 30 a support shaft is
pressed. On the support shaft 31 is formed a knurled section 31a,
by which the support shaft 31 is securely connected to the valve
body 30. Also, at the center of the outer side of the case 20, a
bearing 32 is pressed in. In this case, the clearance accuracy is
lower than that of the cylindrical valve, but a necessary clearance
accuracy is obtainable by installing a unitized valve body and case
assembly.
Many embodiments of the present invention have been explained, but
it is to be noted that various variations of the present invention
may be adopted.
Also, the case 20 may be made in a rectangular or tapered
configuration to insure easy installation to the intake
manifold.
Furthermore, an adhesive of good heat conduction may be used at the
mounting section for mounting the bearing 32 to improve heat
conduction in the case the EGR is employed.
The sealing members of the case 20 and the intake manifold 50 may
be other means than the rubber packings, such as adhesive, O-rings,
liquid gasket, baking gaskets, etc. Also, there may be formed a
plurality of grooves on both the case side and the manifold side to
form labyrinth packings.
Furthermore, airtightness may be kept by such a construction that
the case is formed of a resinous material, on the surface of which
a projecting part is formed, and the projecting part is pressed
into firm contact with the intake manifold.
Furthermore, a means for driving the actuator 40 is not limited
only to the magnetically driving means using electromagnets and
permanent magnets, but various other types of driving means such as
pneumatic, oil hydraulic, electric and other driving means may be
used.
In the above-described embodiment, the intake control valve is
driven between the full-open and full-close positions, but may be
also between the full-close and intermediate opening positions
(e.g., a half opening). For example, according to the actuator
described in detail in the first embodiment, when the magnetic
coils 43a and 43b are not energized, the rotary magnet 42 is held
steady in a specific position by the permanent magnets 44a and 44b;
however, the position of this rotary magnet 42 can be controlled to
a desired position by controlling a magnetomotive force of the
magnetic coil through duty control, at a specific frequency, of a
driving voltage applied to the magnetic coil. The valve body 30 can
be stopped in a half-open state by utilizing this function. Also it
is possible to improve the intake air quantity control accuracy by
driving the intake control valve between the full-close and
half-close positions as compared with the intake control valve
driven between the full-close and full-open positions. That is,
when the intake control valve is driven between the full-close and
full-open positions in an attempt to gain a specific amount of
intake air, the intake control valve must be closed at the valve
time ATDC t1 as illustrated in FIG. 28. However, when the intake
control valve is operated between the full-close and half-open
positions to obtain the specific amount of intake air, it is
sufficient to drive the intake control valve at the timing ATDC t2
as illustrated in FIG. 29. Therefore, since the timing t2 is longer
than the timing t1, it is possible to enhance the accuracy of
control of the amount of intake air to be drawn into the engine
while the intake control valve is open. Furthermore, since the
intake control valve is held open for a long time, the period of
adiabatic expansion during the intake stroke after the closing of
the intake control valve can be decreased; therefore it is possible
to prevent a combustion temperature drop likely to be caused by an
air temperature drop caused by the adiabatic expansion while
maintaining a pumping loss reduction effect. Also since the intake
air flows into the cylinder for a prolonged period of time, an
improvement in fuel combustion by the swirling motion of the
air-fuel mixture can be expected.
FIGS. 28 and 29 are timing charts showing the operation of intake
and exhaust valves operating correspondingly to engine operation
cycles, an air pressure upstream of the intake valve, and the
operation of the intake control valve.
In FIGS. 28 and 29, the intake control valve opens at a timing
largely advanced more than the intake valve opening timing; when
the intake valve begins opening, the pressure upstream of the
intake valve has risen nearly to and stabilized at the atmospheric
pressure. Therefore, when the intake valve opens, the engine draws
in the air at the atmospheric pressure. The amount of the intake
air to be drawn into the engine can not be controlled below the
amount of air to be determined by the volume of the intake air
passage between the intake control valve and the intake valve and
the atmospheric pressure. Therefore, a less amount of intake air
may be realized by controlling the intake pressure upstream of the
intake valve below the atmospheric pressure at the time of opening
of the intake valve by retarding the intake control valve opening
timing. For example, as shown in FIG. 30, it is possible to set the
intake control valve opening timing to immediately before the
intake control valve begins to open, so that the intake valve may
begin to open before the intake pressure upstream of the intake
valve reaches the atmospheric pressure. Thence it becomes possible
to reduce the amount of the intake air to be supplied into the
engine, and accordingly to perform a high-accuracy control of a
small amount of intake air under a low-load condition, or under an
idling condition.
The intake control device of the present invention can be used as a
device mounted in the intake air passage of an internal combustion
engine for controlling the intake period and the amount of intake
air to be supplied into the cylinders of the engine; particularly
the device can easily be mounted in the intake air passage, and
facilitate its mounting to the internal combustion engine.
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